java怎么分页显示前端数据 java web实现分页查询

首先在原有的数据库实体bean上在建立一个分页实体bean

/**
 * 用于展示分页数据的Javabean对象
 * @author Lenovo
 *
 */
public class PageenationBean {

	private Integer currPage;//当前页数

	private Integer totalPage;//总页数

	private List<UserBean> dataList;//table的数据	public Integer getCurrPage() {
		return currPage;
	}	public void setCurrPage(Integer currPage) {
		this.currPage = currPage;
	}	public Integer getTotalPage() {
		return totalPage;
	}	public void setTotalPage(Integer totalPage) {
		this.totalPage = totalPage;
	}	public List<UserBean> getDataList() {
		return dataList;
	}	public void setDataList(List<UserBean> dataList) {
		this.dataList = dataList;
	}
}然后在持久层和业务层书写分页查询的方法
持久层：
public interface IUserDao {
 /**
	 * 获取总条数
	 * @return
	 */
	public int getTotalCount();
	/**
	 * 通过起始索引获取数据
	 * @param StartIndex
	 * @return
	 */
	public List<UserBean> getUserListByStartIndex(int StartIndex);业务层：
public interface IUserService {
 
	/**
	 * 获取总页数
	 * @return
	 */
	public int getTotalPage();

	/**
	 * 通过起始索引获取数据
	 * @param StartIndex
	 * @return
	 */
	public List<UserBean> getUserListByCurrPage(int currPage);然后实现接口方法
持久类接口实现：
public class UserDaoImpl extends BaseDao implements IUserDao{
 @Override
	public int getTotalCount() {
		this.setConnection();
		int totalCount = 0;
		try {
			ps = con.prepareStatement("select count(*) from stuscore");
			rs = ps.executeQuery();
			if(rs.next()) {
				totalCount =rs.getInt(1);
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		this.closeConnection();
		return totalCount;
	}	@Override
	public List<UserBean> getUserListByStartIndex(int StartIndex) {
		List<UserBean> list = new ArrayList<UserBean>();
		this.setConnection();
		try {
			ps = con.prepareStatement("select * from stuscore limit ?,5");
			ps.setInt(1, StartIndex);
			rs=ps.executeQuery();
			while(rs.next()) {
				UserBean user=new UserBean();
				user.setId(rs.getInt("id"));
				user.setName(rs.getString("name"));
				user.setGrade(rs.getString("grade"));
				user.setSex(rs.getString("sex"));
				user.setAge(rs.getInt("age"));
				user.setScore(rs.getInt("score"));
				list.add(user);
			}

		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			this.closeConnection();
		}
		return list;
	}业务类接口实现：
public class UserServiceImpl implements IUserService{
 private IUserDao dao= new UserDaoImpl();
	@Override
	public int getTotalPage() {
		//得到数据总条数
		int totalCount= dao.getTotalCount();
		//计算总页数公式：totalPage	= (totalCount + pageSize	-1)/pageSize
		int totalPage = (totalCount+5-1)/5;
		return totalPage;
	}	@Override
	public List<UserBean> getUserListByCurrPage(int currPage) {
		//通过当前页计算起始索引
		int startIndex = (currPage-1)*5;
		//通过起始索引查询数据
		List<UserBean> userList =dao.getUserListByStartIndex(startIndex);
		return userList;
	}然后 书写servlet方法
@WebServlet("/ShowUserListServlets")
public class ShowUserListServlets extends HttpServlet {

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		//动态获取当前第几页并做计算
		String operation = request.getParameter("operation");
		String currPageStr = request.getParameter("currPage");
		int currPage = 1;
		//调取业务层查询数据
		IUserService service= new UserServiceImpl();
		//获取总页数
		int totalPage = service.getTotalPage();
		if(currPageStr == null) {
			currPage = 1;
		}else if("首页".equals(operation)){
			currPage = 1;
		}else if("上一页".equals(operation)) {
			currPage = Integer.parseInt(currPageStr)-1;
			if(currPage <= 0) {
				currPage = 1;
			}
		}else if("下一页".equals(operation)) {
			currPage = Integer.parseInt(currPageStr)+1;
			if(currPage >= totalPage) {
				currPage = totalPage;
			}
		}

		List<UserBean> userList = service.getUserListByCurrPage(currPage);

		//构建javabean对象-PagenationBean
		PageenationBean pagenationBean = new PageenationBean();
		pagenationBean.setCurrPage(currPage);
		pagenationBean.setTotalPage(totalPage);
		pagenationBean.setDataList(userList);

		//放入作用域
		request.setAttribute("page", pagenationBean);
		request.getRequestDispatcher("userList.jsp").forward(request, response);
	}	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}最后用将jsp作为显示
<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>
	<table border="2" style="color:red,border-collapse: collapse;">
		<tr>
		<th>学号</th>
		<th>姓名</th>
		<th>性别</th>
		<th>年龄</th>
		</tr>
		<c:forEach items="${page.dataList }" var="u">
		<tr>
		<td>${u.id }</td>
		<td>${u.name }</td>
		<td>${u.sex}</td>
		<td>${u.age}</td>
		</tr>
	</c:forEach>
	</table>
	<h3>
		第${page.currPage }页/共${page.totalPage }页
	</h3>
	<br>
	<form action="ShowUserListServlets" method="get">
		<input type="submit" value="首页" name="operation">
		<input type="submit" value="上一页" name="operation">
		<input type="submit" value="下一页" name="operation">
		<input type="submit" value="尾页" name="operation">
		<%--隐藏表单域作用，记录当前是第几页 --%>
		<input type="hidden" name="currPage" value="${page.currPage }" >
		<hr>
		班级：<input type="text" name="class"><br>
		性别：<input type="text" name="sex"><br>
		成绩段：
		<input type="text" name="min">至
		<input type="text" name="max"><br>
		<input type="submit" value="查询">
	</form>
</body>
</html>